JPH09276931A - Method for coiling hot rolled steel strip and device for coiling hot rolled steel strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To coil a hot rolled steel strip in the normal state. SOLUTION: The roll gap between an upper pinch roll 22 and a lower pinch roll 23 of a pinch roll unit 21 for feeding the strip 2 rolled with a finishing mill 1 to a down coiler 11 is set more than the thickness of the strip 2, the screw-down pressure of the pinch roll unit 21 at the time of biting the strip 2 into the pinch roll unit 21 is set higher than the screw-down pressure during coiling with a down coiler 11 and the screw-down pressure of the pinch roll unit 21 is adjusted so that the screw-down pressure corresponds to coiling tension when the coiling tension is generated on the strip 2. And, when the rear end part of the strip 2 is passed through the finishing mill 1, the screw-down pressure is adjusted higher than the screw-down pressure during coiling with the down coiler 11 and the strip 2 is coiled in the normal state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winding method and a winding device for winding a hot rolled steel strip rolled by a finish rolling mill in a coiler.

[0002]

2. Description of the Related Art FIG. 6 shows a schematic side view of a winding portion of a general hot rolling facility. The hot-rolled steel strip (strip) 2 finish-rolled by the finish rolling mill 1 is cooled to a required temperature by a cooling spray (not shown), and a crop at a tip end is cut by a crop shear (not shown). It is adapted to be conveyed to the pinch roll unit 4. The pinch roll unit 4 raises and lowers the upper pinch roll 7 via the frame 6 by the screw jack 5 to set the gap between the lower pinch roll 9 and the plate thickness of the strip 2. When the upper pinch roll 7 and the lower pinch roll 9 bite the tip of the strip 2, the air cylinder 10 causes the strip 8 to move.
Is reduced to a predetermined pressure and supplied to the down coiler 11.

In the down coiler 11, the mandrel 12 and the first unit roller 13 bite the tip of the strip 2 and press the strip 2 with the first unit roller 13, the second unit roller 14 and the third unit roller 15. Roll up. After the second roll, the first unit roller 13, the second unit roller 14, and the third unit roller 15 are successively controlled to avoid a step difference to prevent the top end mark from being generated, and the coil is drawn as indicated by a two-dot chain line in the figure. Roll up to 16.

[0004]

The conventional winding of the strip 2 has the following problems. Since the gap between the upper pinch roll 7 and the lower pinch roll 9 is made smaller than the plate thickness of the strip 2 and the tip end of the strip 2 is engaged, the air cylinder 10 is used to alleviate the impact at the time of engagement. It has been suppressed. Since the air cylinder 10 cannot adjust the pressure reduction during winding, the strip 2 is always pressed down at a constant pressure during winding by the down coiler 11. Therefore, when the strip 2 is bitten by the upper pinch roll 7 and the lower pinch roll 9, the strip 2 is instantaneously pressed down with a strong pressing force, so that centering of the strip 2 due to the short stroke operation of the side guide may be suppressed. there were. Normally, when winding the strip 2, the mandrel 1
2 is rotating faster than the feed rate of strip 2 (high lead rate). Therefore, the mandrel lead energy is absorbed by the strip 2 at the moment when the strip 2 is wound around the mandrel 12 and a tension is generated, and the necking rate of the strip 2 increases due to the variation in the tension. The trailing end of the strip 2 slips out of the finish rolling mill 1 and slipping of the strip 2 occurs between the upper pinch roll 7 and the lower pinch roll 9 due to the winding tension of the down coiler 11 having a high lead rate. The tension for winding could be insufficient.

[0005]

In order to solve the above problems, a method for winding hot strip steel according to the present invention is a roll of a pinch roll for feeding hot strip steel rolled by a finish rolling mill to a coiler. An interval is set to a plate thickness of the hot-rolled steel strip or more, and a rolling-down pressure of the pinch roll at the time of biting into the pinch roll of the hot-rolled steel strip is reduced by winding the pinch roll in the coiler. It is set higher than the pressure, and when the winding tension occurs in the hot-rolled steel strip, the rolling-down pressure of the pinch roll is adjusted to a rolling-down pressure commensurate with the winding tension, and the rear end of the hot-rolled steel strip is It is characterized in that the pressure of the pinch rolls is adjusted to be higher than the pressure of the pinch rolls being wound by the coiler when leaving the finishing mill.

Further, the hot-rolled steel coiling device of the present invention for solving the above problems adjusts the roll interval of the pinch rolls for supplying the hot-rolled steel rolled by the finish rolling mill to the coiler. And a rolling-down pressure setting means for setting a rolling-down pressure, a biting detection means for detecting biting of the hot-rolled steel into the pinch roll, and a winding tension for detecting a winding tension of the hot-rolled steel. Detecting means, trailing edge detecting means for detecting that the rear end portion of the hot-rolled steel strip has passed through the finish rolling mill, and biting detection means for biting the hot-rolled steel strip into the pinch roll When the reduction pressure of the pinch roll is detected is higher than the reduction pressure of the pinch roll during winding in the coiler, the reduction pressure setting means is operated and the winding tension detection means is used. When it is detected that a winding tension is generated on the strip steel, the rolling pressure setting means is operated so that the rolling pressure of the pinch roll becomes a rolling pressure commensurate with the winding tension, and the trailing edge detecting means is further operated. According to this, when it is detected that the rear end of the hot-rolled steel strip has passed through the finish rolling mill, the reduction pressure of the pinch roll becomes higher than the reduction pressure of the pinch roll during winding in the coiler. Thus, the control means for operating the reduction pressure setting means is provided.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION At the start of winding hot-rolled steel (strip), the servo valve and the pressure reduction cylinder are used as position control, and the servo valve operates the pressure reduction cylinder while detecting the rod position of the pressure reduction cylinder. By setting the roll interval of the pinch rolls which is the same as or larger than the plate thickness, the leading end of the strip is caught, and the centering effect of the strip due to the short stroke operation of the side guide is improved.

When the pinch roll unit bites the strip, the servo valve and the pressure reduction cylinder are switched to pressure reduction control, the pressure reduction cylinder is operated by the servo valve while detecting the pressure reduction pressure, and the pressure reduction pressure is made larger than that during winding. By feeding the coiler to the coiler and starting the winding, a sudden increase in tension at the start of winding is prevented from being transmitted to the finishing rolling mill to reduce the amount of strip necking.

When tension is generated in the strip due to the winding, the stripping is adjusted to an optimum rolling pressure corresponding to the winding tension in the strip thickness, material and strip width, and the coil is wound into the coil. When the rear end of the strip slips out of the finish rolling mill, the rolling pressure is made higher than that during winding, preventing slippage between the strip and pinch roll due to the winding tension of the coiler with a large lead rate,
Ensure normal strip tension.

[0010]

FIG. 1 is a side view of a hot-rolled steel coiling device according to an embodiment of the present invention, FIG. 2 is a block diagram of a control device, and FIG. 3 is a graph showing the transition of rolling pressure. 4, Figure 5
A flowchart showing the action of pinch roll is shown in FIG. Note that the same members as those shown in FIG. 6 are denoted by the same reference numerals, and redundant description is omitted.

In FIG. 1, reference numeral 21 is a pinch roll unit for supplying the hot-rolled steel strip (strip) 2 rolled by the finish rolling mill 1 to the down coiler 11. The pinch roll unit 21 is an upper pinch roll that is driven to rotate. 22 and a lower pinch roll 23. Upper pinch roll 2
2 is supported by a hydraulic pressure reduction cylinder 24, and the rod position of the pressure reduction cylinder 24 is detected by a Silnack sensor 25. The upper pinch roll 22 is moved up and down by driving the pressure-reducing cylinder 24, and the up-and-down state is detected by the sillnack sensor 25.

The pressure reduction cylinder 24 has hydraulic pressure sensors 26, 2
A servo valve 28 is attached via 7, and the hydraulic pressure sensors 26 and 27 and the servo valve 28 are electrically connected to a control device 29. In addition, a bite detection unit 30 that detects that the tip of the strip 2 is bitten by the upper pinch roll 22 and the lower pinch roll 23, and that the rear end of the strip 2 has come out of the finish rolling mill 1 is detected. The trailing edge detecting means 31 and the winding tension detecting means 32 for detecting the occurrence of the winding tension on the strip 2 are provided, and the bite detecting means 30, the trailing edge detecting means 31, and the winding tension detecting means 32 are provided. Are electrically connected to the control device 29. The control device 29 will be described with reference to FIG.

In FIG. 2, 33 is the upper pinch roll 22.
And a lower pinch roll 23 is a pinch roll gap calculation processing unit. The pinch roll gap calculation processing unit 33 receives the detection signal from the Silnack sensor 25 and transmits the calculation result to the gap / pressure reduction pressure comparison calculation unit 34. Reference numeral 35 denotes a pinch roll pressure reduction calculation processing unit. The pinch roll pressure reduction calculation processing unit 35 receives detection signals from the hydraulic pressure sensors 26 and 27 and transmits the calculation result to the gap / pressure reduction pressure comparison calculation unit 34. Also, 36
Is a gap / reduction pressure storage unit, and the gap / reduction pressure storage unit 36 receives a signal from the gap / reduction pressure calculation processing unit 37, and the gap / reduction pressure comparison calculation unit 34.
Send a signal to. 38 is a servo valve operation instructing section,
The servo valve actuation instruction unit 38 receives a signal from the gap / pressure reduction pressure comparison operation unit 34 and actuates the servo valve 28.

A pinch roll gap calculation processing unit 33, a gap / pressure reduction pressure comparison calculation unit 34, a pinch roll reduction pressure calculation processing unit 35, a gap / pressure reduction pressure storage unit 36, a gap / pressure reduction pressure calculation processing unit 37, and a servo valve operation instruction. Control unit 29 having reduction pressure setting means by section 38
Is configured.

A method of winding the strip 2 with the above-described hot-rolled steel coiling device will be described with reference to FIGS. 4 and 5.

When the strip 2 is wound up, first, the pressure control of the upper pinch roll 22 is used as the position control, and the plate thickness, material and plate width of the strip 2 are input to the gap / pressure reduction pressure calculation processing section 37. The gap / roll-down pressure calculation processing unit 37 uses the input data to determine the pinch roll unit 21.
The distance between the upper pinch roll 22 and the lower pinch roll 23, that is, the roll gap is calculated. The gap / roll-down pressure calculation processing unit 37, depending on the input data, is a roll-down pressure during winding, a roll-down pressure higher than the roll-down pressure during winding, and higher than the roll-down pressure during winding. Calculate the reduction pressure when slipping out. gap·
Each rolled pressure calculated by the rolled pressure calculation processing unit 37 is input to and stored in the gap / rolled pressure storage unit 36.

On the other hand, the detection signal of the rod position from the sillnac sensor 25 is a pinch roll gap calculation processing unit 33.
The pinch roll gap calculation processing unit 33 calculates the size of the roll gap based on this signal. The dimension of the roll gap calculated by the pinch roll gap calculation processing unit 33 is input to the gap / pressure reduction pressure comparison calculation unit 34, and the gap / pressure reduction pressure comparison calculation unit 34 inputs the input roll gap dimension and the gap / pressure reduction pressure. The size of the required roll gap stored in the storage unit 36 is compared and calculated. Based on the result of the comparison operation, the servo valve 2
8 to operate the reduction cylinder 24 to remove the strip 2
A roll gap having the same size as or larger than the plate thickness of is set so that the leading end of the strip 2 is engaged, and the centering effect of the strip 2 by the short stroke operation of the side guide (not shown) is improved. The bite at the tip of the strip 2 is detected by the bite detection means 30.

Next, the pressure reduction of the upper pinch roll 22 is switched to the pressure control. The hydraulic pressure states of the head side and the rod side of the pressure reduction cylinder 24 are detected by the hydraulic pressure sensors 27 and 28, and are input to the pinch roll pressure reduction calculation processing unit 35. In the pinch roll pressure reduction processing unit 35, the head side and the rod side are detected. The pressure reduction of the upper pinch roll 22 is calculated by the hydraulic pressure difference. The calculated pressure reduction of the upper pinch roll 22 is input to the gap / pressure reduction pressure comparison calculation unit 34, and the gap / pressure reduction pressure comparison calculation unit 34 calculates the pressure reduction of the upper pinch roll 22 and the gap / pressure reduction storage unit. Three
The rolling reduction pressure at the time of biting stored in 6 is compared and calculated. Based on the result of the comparison calculation, the reduction valve 24 is operated by the servo valve 28 to adjust it to a required reduction pressure, that is, a reduction pressure higher than the reduction pressure during winding, and the strip 2 is supplied to the down coiler 11. In the down coiler 11, the strip 2 is connected to the mandrel 12 and the first
The unit roller 13 is bitten to prevent a sudden increase in tension at the start of winding from being transmitted to the finishing rolling mill 1 and reduce the necking amount of the strip 2.

When the winding tension detecting means 32 detects that tension has been generated in the strip 2 by winding, the pinch roll pressure reduction processing unit 35 calculates it based on the signals of the hydraulic pressure sensors 27 and 28. The rolled pressure is compared with the rolled pressure stored in the gap / rolled pressure storage unit 36 during winding. Based on the result of the comparison calculation, the reduction valve 24 is operated by the servo valve 28, and the reduction pressure is adjusted to an optimum reduction pressure corresponding to the winding tension. In the down coiler 11, the first unit roller 1
3, second unit roller 14 and third unit roller 1
The coil 16 is wound around by the pressing at 5 and the step avoidance control.

When the trailing edge detecting means 31 detects that the rear end of the strip 2 has come out of the finish rolling mill 1 near the end of the winding of the strip 2, the pinch roll down pressure calculation processing section 35. , Oil pressure sensor 27, 28
The pressure reduction pressure calculated based on the signal is compared with the pressure reduction pressure in the gap / pressure reduction pressure storage unit 36 at the time of slippage. Based on the result of the comparison calculation, the reduction valve 24 is operated by the servo valve 28 to adjust the reduction pressure to a required reduction pressure, that is, a reduction pressure higher than the reduction pressure during winding, to reduce the strip 2. As a result, slippage between the upper pinch roll 22 and the lower pinch roll 23 of the strip 2 due to the winding tension of the down coiler 11 having a high lead rate is prevented, and the normal winding tension of the strip 2 is maintained.

The relationship between the pressure reduction and the winding state of the strip 2 in the above-described winding method, that is, the state of transition of the pressure reduction is as shown in FIG.

[0022]

With the method and apparatus for winding hot-rolled steel according to the present invention, the reduction pressure during winding of the hot-rolled steel can be adjusted, so that the following effects are achieved. Since the distance between the pinch rolls is set to be equal to or greater than the plate thickness of the hot rolled steel strip and the tip of the hot rolled steel strip is caught in the pinch roll
The centering effect of the hot-rolled steel by the short stroke operation of the side guide can be improved. When the pinch roll bites the tip of the hot-rolled steel strip, the rolling pressure is made higher than the rolling-down pressure during winding, and the hot-rolled steel strip is supplied to the coiler. It is possible to prevent the increase from being transmitted to the finish rolling mill and reduce the necking amount of the hot-rolled steel strip. When hot strip steel slips out of the finishing mill, the rolling pressure is made higher than the rolling pressure during winding to prevent slippage between the hot strip steel and pinch roll due to the winding tension of the coiler with a large lead rate. Therefore, the winding tension of the hot-rolled steel can be normally maintained.

[Brief description of drawings]

FIG. 1 is a side view of a hot-rolled steel winding device according to an embodiment of the present invention.

FIG. 2 is a configuration block diagram of a control device.

FIG. 3 is a graph showing a transition of rolling pressure.

FIG. 4 is a flowchart showing the action of pinch roll.

FIG. 5 is a flowchart showing the action of pinch roll.

FIG. 6 is a schematic side view of a winding unit of a general hot rolling facility.

[Explanation of symbols]

 1 Finishing Rolling Machine 2 Hot Strip Steel (Strip) 11 Downcoiler 12 Mandrel 13 1st Unit Roller 14 2nd Unit Roller 15 3rd Unit Roller 16 Coil 21 Pinch Roll Unit 22 Upper Pinch Roll 23 Lower Pinch Roll 24 Lowering Cylinder 25 Sill Nack sensor 26, 27 Oil pressure sensor 28 Servo valve 29 Control device 30 Entrapment detection means 31 Bottom slippage detection means 32 Winding tension detection means 33 Pinch roll gap calculation processing unit 34 Gap / pressure reduction pressure comparison calculation unit 35 Pinch roll pressure reduction calculation Processing unit 36 Gap / reduction pressure storage unit 37 Gap / reduction pressure calculation processing unit 38 Servo valve operation instructing unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuhisa Miyaguchi 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries Ltd. Hiroshima Works (72) Inventor Ryuichi Ohzono 4 Kannon-shinmachi, Nishi-ku, Hiroshima-shi, Hiroshima 6-22 No. 22 Hiroshima Factory of Mitsubishi Heavy Industries, Ltd.

Claims (2)

[Claims] 1. A roll interval of a pinch roll for supplying a hot-rolled steel strip rolled by a finish rolling mill to a coiler is set to a plate thickness of the hot-rolled steel strip or more, and the pinch of the hot-rolled steel strip is set. The pressure of the pinch roll at the time of biting into the roll is set to be higher than the pressure of the pinch roll during winding in the coiler, and the pinch is generated when a winding tension occurs in the hot-rolled steel. The rolling pressure is adjusted to a rolling pressure corresponding to the winding tension, and when the trailing end of the hot-rolled steel strip passes through the finishing mill, the rolling pressure of the pinch roll is adjusted by the coiler during winding. A method for winding hot-rolled steel, comprising adjusting the rolling pressure to be higher than the rolling pressure of the pinch roll. 2. A reduction pressure setting means for adjusting a roll interval of pinch rolls for setting a reduction pressure for supplying the hot rolled steel strip rolled by a finish rolling mill to a coiler; A bite detection means for detecting biting into a pinch roll, a winding tension detection means for detecting a winding tension of the hot-rolled steel strip, and a rear end portion of the hot-rolled steel strip exits the finish rolling mill. That the pinching roll of the hot rolled strip steel is caught by the pinch roll by the pinch roll detection unit that detects that the pinch roll is being wound by the coiler. Of the pinch roll is operated so that the rolling pressure is higher than the rolling pressure of the pinch roll, and when the winding tension detecting means detects that the winding tension is generated in the hot-rolled steel strip, The rolling pressure setting means is operated so that the rolling pressure of the roll becomes a rolling pressure commensurate with the winding tension, and the trailing edge portion of the hot-rolled steel strip has passed through the finish rolling mill by the trailing edge detection means. When it is detected that the pressure reduction pressure of the pinch roll is higher than the pressure reduction pressure of the pinch roll during winding in the coiler, the control means for operating the pressure reduction pressure setting means. Characteristic hot rolling steel winding device.